SU1651809A1 - Apparatus for simulating hydrodynamic field of a fishing gear - Google Patents

Abstract

The invention relates to industrial fisheries and can be used to simulate the hydrodynamic field of a piece of fishing gear, having the form of a rotating pick, consisting of segments of cables of different diameters and streamlined water flow. The purpose of the invention is to improve the accuracy of modeling the field created by the selection in the water flow. The frame of the device is made in the form of a vertical shield 1 with openings 2. Conductors 4 are located on the surface of shield 1 along a trajectory corresponding to the location of the selections in the stream. The ends of the conductors 4 are passed through the holes 2 and are provided with clamps 3. The conductors 4 are separated from each other and are connected in series to the alternating voltage source by wires 6 perpendicular to the plane of the shield 1. When current passes through the conductors 4, the resulting field corresponds to the hydrodynamic field created in the flow of rebounds. 2 Il. Q S Fig1

Description

The invention relates to industrial fishing and can be used to simulate the hydrodynamic field created by selection in the flow of water. ,

The purpose of the invention is to improve the accuracy in modeling the floor created by fittings.

FIG. 1 shows the proposed device; in fig. 2 shows the layout of the conductors.

The device comprises a frame made of a dielectric material (for example, wood), having the form of a vertical shield 1. The shield is made with holes 2. On one side with holes 2, clamps 3, each made in the form of rings with slats (not shown), are fixed, fixed at the ends of the conductors 4, passed into the holes 2 and located on the surface of the frame corresponding to the surface of the part | (rebounds). Monolayer windings 5 are applied to the lateral surface of the conductors 4. The conductors 4 can be attached to the shield 1 with adhesive tape | (not shown).

The connecting wires 6 are connected in series to the ends of the conductors 4 and are located perpendicular to the plane of the shield 1. The conductors 4 are connected through the wires 6 by means of the conductors 7 and 8 to the output of an alternating voltage source - a sound generator 9,

The device works as follows.

Pre-select a linear modeling scale equal to

L

where L is the length of the detail fishing gear

(for example, rebounds); 1 - length of conductors af. The shape of the rotating upper and lower pickup is then determined (calculated, simulated, etc.), which, when towed, takes up a vertical position. On the shield 1, on a scale m, draw a form of presumerism af and a f and drill holes 2 at points a, b, cs d, b, f, a, b, c, d, er, f. EC - if the diameters of the cable lengths, the cuts are reduced from the center, the cuts to its ends, then the conductors 4 with a length of cd,

be, af, c d, b c, a f are fastened to the shield 1, their ends are located at the corresponding holes 2. The ends of the conductors 4 are provided with clamps 3 with a strap and connected to the connecting wires 6 (figure 1). If the diameters of the segments of the climbs increase from the center of the clips to its ends, then

n conductors 4 with the length ab, ac, af, fe, fd, a b, a c1, a f, f e, f d sa are fastened on the shield 1 (figure 2).

FIG. 1 and FIG. 2 segments of conductors 4 for clarity are separated, but on

in fact, they are combined and secured with adhesive tape and are located along a trajectory shaped like a fit, determined by calculation, etc. The conductors 4 through the connecting wires 6 are connected by wires 7 and 8 to the output of the sound generator 9.

With the passage of alternating current through the conductors 4 (in the experiments, the frequency of 800-1000 Hz was chosen) around them

c, there is an alternating magnetic field H, which simulates the hydrodynamic field caused by the velocities W, arising when the flow of a piece of a fishing gear that has the shape of a rotating selection.

0 At similar points of the geometrically similar regions of the magnetic and hydrodynamic fields of the induced velocities, the equality

0

Nl

ia

H1 V

where wj and 1 „are caused by speeds in

any two points; N. and H „- intensity at the similar points of the magnetic field„

The measurement of the intensity of the AC magnetic field is carried out by one of the known methods, in particular with the aid of a calibrated measuring coil with a cross section of S cm2 and the number of turns of CO. The constant of such a coil S CO is expressed in square centimeters. The coil is placed in the field of interest and a voltmeter (not shown) measures the induced emf in the coil, which varies according to a sinusoidal law determined by the expression

55

E 4,44 f f WITH,

where E is the amplitude of the EMF induced in the coil;

f

f with

5165

- coil magnetic flux;

- frequency of sinusoidal alternating current;

- the number of turns of the measuring coil.

Since the magnetic flux penetrating the coil is equal to the magnetic permeability of air - (H 1, the magnitude of the EMF amplitude is E 4.4 / HfSW, the magnitude of the voltage is equal to

H

4.44 f SO)

With a constant characteristic of the SfO coil, expressed in cm2, and the measurement of E in volts, the intensity H of the magnetic field is established by expressing SI (A / m).

In order not to recalculate the measured value of the emf to the value of W, then a calibration curve of the voltmeter readings in the values of the induced velocities is constructed in advance by measurements in a field of known intensity. i

When changing the floor measuring

The coil is placed at various points on several planes (parallel and perpendicular) around the model and measured at these points.

On a sheet of graph paper, the field is cut along the measurement plane, mapped to them at appropriate points as the measurement results, and a spatial picture of the floor is obtained from the set of measurements in these planes.

8096

The proposed device (in comparison with the known ones) is simply constructive, it does not require special equipment for its service, while at the same time providing the study and demonstration in the training audience of a volumetric hydrodynamic field caused by the speeds of parts of fishing gear,

Q shaped rotating selection,

consisting of segments of cables of different diameters, streamlined by a stream of water. Improving the accuracy of the simulation is provided by the shape of the device,

Claims (1)

5 similar to the form of full-scale selection, and the simulation of rotating segments, the corresponding lengths of conductors. The invention The device for modeling the hydrodynamic field of a tool part containing a frame made of a dielectric material, conductors located on the surface of the frame corresponding to the surface of the part, interconnected and connected in series to the alternating voltage source using connecting wires whose length is at least three device lengths, clamps, 0 five 0 35 characterized in that, in order to increase the accuracy in modeling the field created by the selection, the frame is made in the form of a vertical shield with holes, the fixings are fixed on the ends of the conductors, the ends of the latter are passed in the shield holes, and the connecting wires are perpendicular to the shield plane. FIG. g